$250 \, mL$,$6 \, M$ $HCl$ and $350 \, mL$,$8 \, M$ $HNO_3$ are mixed with water to make the strength of the resulting solution $3 \, N$. What is the volume of water added? $mL$

The number of oxygen atoms in a solution prepared by dissolving $34.2 \ g$ of sucrose in $90 \ g$ of water is:

Calculate the number of moles of $NaOH$ required to completely neutralize $100 \ g$ of $118\%$ oleum.

The density of a liquid is $1.5 \, g/mL$. There are $50 \, drops$ in $5 \, mL$. The number of molecules in $1 \, drop$ is (molecular weight of liquid is $100$).

What volume of $NH_3$ gas at $STP$ would be needed to prepare $100 \ mL$ of $2.5$ molal $(2.5 \ m)$ ammonium hydroxide solution? (Assume the density of the solution is $1 \ g/mL$)

If the density of liquid water is $1.0 \, g \cdot cm^{-3}$ and the density of water vapor is $0.0006 \, g \cdot cm^{-3}$ at $100 \, ^\circ C$ and $1 \, atm$ pressure,then what is the volume occupied by water molecules in $1 \, L$ of steam at the same temperature in $cm^3$?